Ruby Walsh will team up with Paul Nicholls in a Grade One event for the first time since April 2013 when he takes the ride on the veteran chaser Tidal Bay in Sunday's Hennessy Gold Cup, Ireland's most prestigious chase, at Leopardstown.

Walsh became available to ride Tidal Bay only when Rubi Ball, trained by his new principal employer Willie Mullins, was ruled out of the race shortly before Tuesday's five-day declarations after returning lame from a schooling session. He has ridden only twice for Nicholls since deciding to base himself in Ireland for the 2013-14 season but the opportunity to book Walsh appears to have been a significant factor for Nicholls in deciding to run Tidal Bay at Leopardstown rather than in the Denman Chase at Newbury the previous day.

"We've decided to go to Ireland with Tidal," Nicholls said on Tuesday. "It's a small field, good prize money, he's one from one at the track [when winning the Grade One Lexus Chase in December 2012] and he'll get his ground. Of course, Ruby being available also helps, so it has worked out for us."

Walsh and Nicholls enjoyed a decade of consistent success in Grade One events between 2003 and 2013 thanks to such horses as Kauto Star, Denman, Master Minded and Big Buck's. The last Grade One runner for trainer and jockey was Kauto Stone, who was pulled up in the Punchestown Gold Cup in April 2013, while their most recent Grade One success was Zarkandar's victory in the Aintree Hurdle at last season's Grand National meeting.

Tidal Bay's Grade One wins date back to the Arkle Trophy at the 2008 Cheltenham Festival, when he was trained by Howard Johnson, and, though he is now 13, he shows few signs of feeling his age.

His performance under 11st 12lb in December's Welsh National, when he was a close third behind opponents with 10 stone on their backs, was one of the finest weight-carrying performances of recent seasons and has earned him plenty of respect from bookmakers for Sunday's race. Tidal Bay is the 4-1 joint second-favourite with Last Instalment at the best available prices, in a market headed by Mouse Morris's First Lieutenant at 2-1.

The unexpected absence of Rubi Ball has left Mullins without a runner in the feature race on Sunday's card but he and Walsh could dominate the remainder of Ireland's most important afternoon of Cheltenham Festival trials. The Hennessy is just one of four Grade One events at Leopardstown and Mullins will saddle leading contenders in the other three.

Mullins's five entries for the Deloitte Novice Hurdle include Vatour, a recent Grade Two winner at Punchestown, and his possible opponents include Philip Fenton's The Tullow Tank, ante-post favourite for the Supreme Novice Hurdle at Cheltenham.

Ivan Grozny, favourite for the Triumph Hurdle, will line up for the Spring Juvenile Hurdle which opens the card, while Champagne Fever, last year's winner of the Supreme Novice Hurdle, is among seven entries for the Grade One Dr PJ Moriarty Memorial Chase over two miles and five furlongs.

One notable absentee from the entries on Sunday is Salsify, the winner of the last two renewals of the Foxhunters' Chase at Cheltenham in March.

"He's not running Sunday as he knocked a joint in a gallop last Tuesday," Rodger Sweeney, Salsify's trainer, said. "He's missed his last two pieces of work and if he misses it next week then he won't be going to Cheltenham, you can't go there unless you are 100% fit. So, the dream is dashed at the minute but that's horses for you."